================================================================== BUG: KASAN: use-after-free in get_disk_and_module block/genhd.c:1787 [inline] BUG: KASAN: use-after-free in exact_lock+0x38/0xd0 block/genhd.c:677 Read of size 8 at addr ffff8881009ad460 by task syz.0.8436/31148 CPU: 1 PID: 31148 Comm: syz.0.8436 Tainted: G W 5.10.234-syzkaller-00023-g3f5f2283d684 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118 print_address_description+0x81/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0x179/0x1c0 mm/kasan/report.c:452 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 get_disk_and_module block/genhd.c:1787 [inline] exact_lock+0x38/0xd0 block/genhd.c:677 kobj_lookup+0x294/0x430 drivers/base/map.c:119 get_gendisk+0xf7/0x3d0 block/genhd.c:1001 bdev_get_gendisk fs/block_dev.c:1110 [inline] __blkdev_get+0x18c/0x12f0 fs/block_dev.c:1474 blkdev_get fs/block_dev.c:1653 [inline] blkdev_open+0x241/0x480 fs/block_dev.c:1770 do_dentry_open+0x7c1/0x10d0 fs/open.c:819 vfs_open+0x73/0x80 fs/open.c:942 do_open fs/namei.c:3391 [inline] path_openat+0x2660/0x3000 fs/namei.c:3509 do_filp_open+0x21c/0x460 fs/namei.c:3536 do_sys_openat2+0x13f/0x710 fs/open.c:1217 do_sys_open fs/open.c:1233 [inline] __do_sys_creat fs/open.c:1309 [inline] __se_sys_creat fs/open.c:1303 [inline] __x64_sys_creat+0x11f/0x160 fs/open.c:1303 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f46c8abd169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f46c7127038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007f46c8cd5fa0 RCX: 00007f46c8abd169 RDX: 0000000000000000 RSI: 00000000000000d4 RDI: 00004000000000c0 RBP: 00007f46c8b3e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f46c8cd5fa0 R15: 00007ffdc4d273a8 Allocated by task 26397: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] ____kasan_kmalloc+0xdb/0x110 mm/kasan/common.c:509 __kasan_kmalloc+0x9/0x10 mm/kasan/common.c:518 kasan_kmalloc include/linux/kasan.h:254 [inline] kmem_cache_alloc_trace+0x18a/0x2e0 mm/slub.c:2974 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:664 [inline] copy_verifier_state+0x58b/0xbf0 kernel/bpf/verifier.c:913 is_state_visited kernel/bpf/verifier.c:9937 [inline] do_check+0x45ab/0xe8c0 kernel/bpf/verifier.c:10056 do_check_common+0x946/0x1370 kernel/bpf/verifier.c:12047 do_check_main kernel/bpf/verifier.c:12110 [inline] bpf_check+0xb551/0xf230 kernel/bpf/verifier.c:12665 bpf_prog_load kernel/bpf/syscall.c:2239 [inline] __do_sys_bpf kernel/bpf/syscall.c:4440 [inline] __se_sys_bpf+0x107a2/0x11cb0 kernel/bpf/syscall.c:4396 __x64_sys_bpf+0x7b/0x90 kernel/bpf/syscall.c:4396 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb Freed by task 24: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x121/0x160 mm/kasan/common.c:362 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370 kasan_slab_free include/linux/kasan.h:220 [inline] slab_free_hook mm/slub.c:1595 [inline] slab_free_freelist_hook+0xc0/0x190 mm/slub.c:1621 slab_free mm/slub.c:3203 [inline] kfree+0xc3/0x270 mm/slub.c:4191 skb_free_head net/core/skbuff.c:606 [inline] skb_release_data+0x5c6/0x6f0 net/core/skbuff.c:626 skb_release_all net/core/skbuff.c:680 [inline] __kfree_skb net/core/skbuff.c:694 [inline] kfree_skb+0xb9/0x320 net/core/skbuff.c:713 kauditd_hold_skb+0x115/0x200 kernel/audit.c:614 kauditd_send_queue+0x28d/0x2e0 kernel/audit.c:769 kauditd_thread+0x523/0x890 kernel/audit.c:893 kthread+0x34b/0x3d0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff8881009ad000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1120 bytes inside of 2048-byte region [ffff8881009ad000, ffff8881009ad800) The buggy address belongs to the page: page:ffffea0004026a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8881009ac000 pfn:0x1009a8 head:ffffea0004026a00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 ffffea00046c2408 ffffea0004926408 ffff888100042d80 raw: ffff8881009ac000 0000000000080005 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, ts 1765245490, free_ts 0 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x166/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x2d8c/0x2f30 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x435/0xaf0 mm/page_alloc.c:5348 allocate_slab mm/slub.c:1808 [inline] new_slab+0x80/0x400 mm/slub.c:1869 new_slab_objects mm/slub.c:2627 [inline] ___slab_alloc+0x302/0x4b0 mm/slub.c:2791 __slab_alloc+0x63/0xa0 mm/slub.c:2831 slab_alloc_node mm/slub.c:2913 [inline] slab_alloc mm/slub.c:2955 [inline] kmem_cache_alloc_trace+0x1bd/0x2e0 mm/slub.c:2972 kmem_cache_alloc_node_trace include/linux/slab.h:440 [inline] kmalloc_node include/linux/slab.h:570 [inline] kzalloc_node include/linux/slab.h:675 [inline] __alloc_disk_node+0x76/0x570 block/genhd.c:1727 brd_alloc+0x146/0x400 drivers/block/brd.c:394 brd_init+0x125/0x474 drivers/block/brd.c:517 do_one_initcall+0x189/0x620 init/main.c:1197 do_initcall_level+0x186/0x304 init/main.c:1270 do_initcalls+0x4e/0x8e init/main.c:1286 do_basic_setup+0x88/0x91 init/main.c:1306 kernel_init_freeable+0x2be/0x3f5 init/main.c:1510 kernel_init+0x11/0x280 init/main.c:1397 page_owner free stack trace missing Memory state around the buggy address: ffff8881009ad300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881009ad380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881009ad400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881009ad480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881009ad500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================